Myocardial infarction is a multifactoral disease and its development is defined by the interaction between individual's genetic background and various environmental factors (Marenberg M E, Risch N, Berkman L F, Floderus B, de Faire U. Genetic susceptibility to death from coronary heart disease in a study of twins. N Engl J Med 1994; 330:1041-1046., Nora J J, Lortscher R H, Spangler R D, Nora A H, Kimberling W J. Genetic-epidemiologic study of early-onset ischemic heart disease. Circulation 1980; 61: 503-508). In general, the risk of myocardial infarction is increased in proportion to the number of conventional risk factors such as hypertension, diabetes, hyperlipidemia, etc (Nora J J, Lortscher R H, Spangler R D, Nora A H, Kimberling W J. Genetic-epidemiologic study of early-onset ischemic heart disease. Circulation 1980; 61: 503-508). These risk factors themselves are partially regulated by genetic factors. However, since a family history is an independent predictable factor of myocardial infarction, it is suggested that there are genetic factors susceptible for myocardial infarction other than conventional risk factors (Marenberg M E, Risch N, Berkman L F, Floderus B, de Faire U. Genetic susceptibility to death from coronary heart disease in a study of twins. N Engl J Med 1994; 330: 1041-1046). In addition, cases in which myocardial infarction may be developed without any conventional risk factors also suggest the relationship between myocardial infarction and genetic factors.
Myocardial infarction is a disease with the highest mortality in the Western countries. Even in the case where myocardial infarction is not lethal, it may be complicated with heart failure, angina pectoris and refractory arrhythmia, thus deteriorating the quality of life of patients. Therefore, needless to say, it is important to prevent myocardial infarction. One of the methods for preventing myocardial infarction is to identify genes susceptible for myocardial infarction. By linkage analysis (Broeckel U, Hengstenberg C, Mayer B, et al. A comprehensive linkage analysis for myocardial infarction and its related risk factors. Nature genet 2002; 30:210-214) and association studies by candidate genes (Cambien F, Poirier O, Lecerf L, et al. Deletion polymorphism in the gene for angiotensin-converting enzyme is a potent risk factor for myocardial infarction. Nature 1992; 359: 641-644. Weiss E J, Bray P F, Tayback M, et al. A polymorphism of a platelet glycoprotein receptor as an inherited risk factor for coronary thrombosis. N Engl J Med 1996; 334: 1090-1094., Iacoviello L, Di Castelnuovo A, De Knijff P, et al. Polymorphisms in the coagulation factor VII gene and the risk of myocardial infarction. N Engl J Med 1998; 338:79-85., Kuivenhoven J A, Jukema J W, Zwinderman A H, et al. The role of a common variant of the cholesterol ester transfer protein gene in the progression of coronary atherosclerosis. N Engl J Med 1998; 338: 86-93), gene locus on the chromosome and some candidate genes which are associated with myocardial infarction have been identified. Previously, by studies of genetic epidemiology, there have been reported the relationships between the myocardial infarction and gene polymorphisms such as angiotensin converting enzyme (Cambien F, Poirier O, Lecerf L, et al. Deletion polymorphism in the gene for angiotensin-converting enzyme is a potent risk factor for myocardial infarction. Nature 1992; 359: 641-644), platelet glycoprotein IIIa (Weiss E J, Bray P F, Tayback M, et al. A genetical polymorphism of a platelet glycoprotein receptor as an inherited risk factor for coronary thrombosis. N Engl J Med 1996; 334: 1090-1094), blood coagulation factor VII, cholesterol ester transfer protein (Kuivenhoven J A, Jukema J W, Zwinderman A H, et al. The role of a common variant of the cholesterol ester transfer protein gene in the progression of coronary atherosclerosis. N Engl J Med 1998; 338: 86-93), and the like. However, there have been conflicting reports, certain conclusion has never been reached. Furthermore, since different races have different gene polymorphisms, it is important to construct a database as to the relationship between polymorphisms and myocardial infarction in each race.